platform_system_core/init/epoll_test.cpp
Bart Van Assche bc5c4a4659 init/epoll: Make Epoll::Wait() easier to use
Invoke the callback functions from inside Epoll::Wait() instead of
returning a vector with pointers to callback functions. Remove handlers
after handler invocation finished to prevent that self-removal triggers
a use-after-free.

The CL that made Epoll::Wait() return a vector is available at
https://android-review.googlesource.com/c/platform/system/core/+/1112042.

Bug: 213617178
Change-Id: I52c6ade5746a911510746f83802684f2d9cfb429
Signed-off-by: Bart Van Assche <bvanassche@google.com>
2022-10-20 09:32:51 -07:00

70 lines
2.1 KiB
C++

/*
* Copyright (C) 2021 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "epoll.h"
#include <sys/unistd.h>
#include <unordered_set>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <gtest/gtest.h>
namespace android {
namespace init {
std::unordered_set<void*> sValidObjects;
class CatchDtor final {
public:
CatchDtor() { CHECK(sValidObjects.emplace(this).second); }
CatchDtor(const CatchDtor&) { CHECK(sValidObjects.emplace(this).second); }
CatchDtor(const CatchDtor&&) { CHECK(sValidObjects.emplace(this).second); }
~CatchDtor() { CHECK_EQ(sValidObjects.erase(this), size_t{1}); }
};
TEST(epoll, UnregisterHandler) {
Epoll epoll;
ASSERT_RESULT_OK(epoll.Open());
int fds[2];
ASSERT_EQ(pipe(fds), 0);
CatchDtor catch_dtor;
bool handler_invoked = false;
auto handler = [&, catch_dtor]() -> void {
auto result = epoll.UnregisterHandler(fds[0]);
ASSERT_EQ(result.ok(), !handler_invoked);
handler_invoked = true;
// The assert statement below verifies that the UnregisterHandler() call
// above did not destroy the current std::function<> instance.
ASSERT_NE(sValidObjects.find((void*)&catch_dtor), sValidObjects.end());
};
epoll.RegisterHandler(fds[0], std::move(handler));
uint8_t byte = 0xee;
ASSERT_TRUE(android::base::WriteFully(fds[1], &byte, sizeof(byte)));
auto epoll_result = epoll.Wait({});
ASSERT_RESULT_OK(epoll_result);
ASSERT_EQ(*epoll_result, 1);
ASSERT_TRUE(handler_invoked);
}
} // namespace init
} // namespace android